There are a number of different network types, but one prevalent form of network is the peer-to-peer network. A peer-to-peer network is one in which peer machines are networked together and maintain the state of the network via records on the participant machines. In peer-to-peer networks, each end node has broadly the same capabilities, and any node can initiate communications. Typical peer-to-peer networks lack a central server for administration, although hybrid networks do exist. So, generally speaking, the term peer-to-peer refers to a set of technologies that allows a group of computers to directly exchange data and/or services. The distinction between peer-to-peer networks and other network technologies is really more about how the member computers communicate with one another than about the network structure itself. For example, many peer-to-peer networks utilize the Internet for communications, but the Internet can also be used for other types of networking.
FIG. 1 illustrates a prior art peer-to-peer network 100. Network 100 includes a user machine 101 which is a peer machine that desires content that originated from content source 139. User machine 101 includes a peer-to-peer client that facilitates file transfers with other peers in network 100, such as peers 110-119. Network 100 is capable of distributing and maintaining multiple copies of original content from content source 139 on peers 110-129. A problem with prior art peer-to-peer networks such as network 100, is that user 101 may falsely believe, through the peer-to-peer client, that the desired content is available from multiple peers 110-129. However, the user 101 is unaware (as signified by the question marks of FIG. 1) that not all peers 110-129 have actual copies of the desired content. For example, if user 101 requests the desired content from peer 110, peer 110 will send spoofed content to user 101. Or if user 101 requests the desired content from peer 111, peer 111 will send a virus to user 101. Even in the case where user 101 requests the desired content from peer 119, user 101 does not know if the content is an authentic copy of the content generated by content source 139.